As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY LIGHTS TEST FAILS "EPSU UNIT FWD L". REPLACED EPSU AND GOT SAME RESULT, REPLACED BATTERY, NO HELP. REINSTALLED ORG UNITS. IAW TSM BEGAN TO SEARCH FOR SHORTED LIGHTS. FOUND SEAT ROWS 1AB-8ABC ESCAPE PATH LIGHTS INOP. THE EMERG LIGHTS TEST HAS SHOWN REPEAT PROBLEMS WITH THE FED CABIN POWER SUPPLY. AT THE FIRST OPPORTUNITY REPLACE THE 7LP RELAY BOARD AND THE EMERG LIGHT SWITCH 4WL. REPLACED LIGHT BOARD 7LP IAW MM. REPLACED EMERGENCY LIGHT SW 4WL.